NO PREP DIASTEMA CLOSURE APPROACH by GIUSEPPE MARCHETTI

Source ; http://www.styleitaliano.org/no-prep-diastema-closure-approach

DR. GIUSEPPE MARCHETTI

INDIRECT ANTERIORS - LABORATORY - CASES - SHADEGUIDES -EGR CORNER - TIPS AND TRICKS

-----------------------------------------------------------------------------------------------

The post-ortho restorative treatment as a solution to closure of diastemas – which are often associated with microdontia – can involve direct techniques, with the modern composite resins, or indirect techniques, with composites, glass ceramics or the new hybrid materials, in an extremely conservative way.

The indirect techniques can be, nowadays, completely additive in various clinical situation, thanks to the gaps that have to be compensated. Most of the times a prosthetic preparation is, in fact, not necessary for those teeth that are very small and don’t have undercuts. The only peculiarity is the assessment of an insertion axis for the handwork which is, most of the times, buccal.

There are several advantages of not preparing the teeth, e.g. preservation of the present enamel, management and control on the emergence profile, reduction in time of the appointments.

In this scientific article a modern approach is proposed for the solution of microdontia and diastema of upper lateral incisors with a multidisciplinary approach.

Img. 1 - Front view, initial situation.

Img. 2 - The patient R.G. exhibits microdontia of teeth 1.2 and 2.2 and right posterior cross-bite.

Img. 3 - Rotation of tooth 1.3 associates with notable spaces between teeth 1.1, 1.2, 1.3 with right open bite.

Img. 4 - The patient is referred to the orthodontist for a treatment solution of the above listed problems.

Img. 5 - To facilitate the correct closure performed by the orthodontist in order to get the ideal situation for the definitive restorations, composite provisionals are made on 1.2 and 2.2 with no adhesive protocol in order to easily be removed after ortho treatment.

Img. 6 - Detail of provisional restorations (left) and after their removal after ortho treatment.

Img. 7 - Detail of the diastemas of lateral incisors after ortho treatment, front and occlusal view.

Img. 8 - Macro-view, detail of the diastemas.

Img. 9 - Macro-view, detail of the diastemas.

Img. 10 - Face bow and impression registrations for manufacturing of two additive veneers for 1.2 and 2.2.

Img. 11 - Lithium disilicate veneers, pressed and stained.

Img. 12 - Try-in with dedicated try-in pastes: for a correct color evaluation a viscous material layer is, in fact, to be interposed to cover the buccal surface, simulating the presence of the product chosen for cementation.

Img. 13 - Try-in of additive veneers, frontal and occlusal view. Note the complete compensation of diastemas and optimal esthetic integration.

Img. 14 - Veneers are once more tried in with the rubber dam positioned, then cemented one by one.

Img. 15 - Details of the etching procedure and protection of the adjacent teeth from contamination with a transparent matrix and then with teflon. To correctly carry out the adhesion procedure on aprismatic non-prepared enamel it is advisable to start with sand blasting with alumina 50 microns, or prolonged etching for 60 seconds of the buccal surface.

Img. 16 - Universal, last-generation adhesive agent application. The product is very viscous so it’s not polymerized immediately, but together with the chosen cement in order to prevent creation o potentially damaging thicknesses before application of the restoration.

Img. 17 - Etching of the internal surface is done with fluorhydric* acid for 20 seconds. After etching and rinsing, the same universal bonding agent, which also contains silane, is applied without polymerizing.

Img. 18 - The chosen cement is applied on the internal surface of the restoration

Img. 19 - Details of the final cementation procedures after removal of excess and finishing.

Img. 20 - Details of the finished restorations under rubber dam isolation.

Img. 21 - Before and after situations.

Img. 22 - The patient’s smile after treatment.

Img. 23 - One month follow-up.

Img. 24 - Details of morphology and diastema closure.

Img. 25 - One year follow-up. Integration of the additive restorations in the front upper sextant is very good.

*Note that the chemical nomenclature only accepts the following terms for the fluoride etching agent we use in indirect restorative procedures, i.e. fluorhydric acid, hydrofluoric acid or hydrogen fluoride.

Conclusions

Additive techniques are more and more revolutionizing the way of thinking, designing and executing indirect restorative treatments. Preservation of sound dental tissues and of tooth structure that hadn't been previously restored has to be one of the main goals in treatment planning of esthetic and functional cases, when – of course – it is indicated.

Aknowledgements

Thank to. Dr. Renato Cocconi for the ortho treatment and to DT Vincenzo Musella for the lab work.

References

Magne P, Cascione D. Influence of post-etching cleaning and connecting porcelain on the microtensile bond strength of composite resin to feldspathic porcelain. J Prosthet Dent. 2006;96(5):354-61.

Magne P, Douglas WH. Porcelain veneers: dentin bonding optimization and biomimetic recovery of the crown. Int J Prosthodont. 1999;12(2):111-21.

Mangani F, Cerutti A, Putignano A, Bollero R, Madini L. Clinical approach to anterior adhesive restorations using resin composite veneers. Eur J Esthet Dent. 2007;2(2):188-209.

Coachman C, Gürel G, Calamita M, Morimoto S, Paolucci B, Sesma N. The influence of tooth color on preparation design for laminate veneers from a minimally invasive perspective: case report. Int J Periodontics Restorative Dent. 2014;34(4):453-9.

Gürel G, Sesma N, Calamita MA, Coachman C, Morimoto S. Influence of enamel preservation on failure rates of porcelain laminate veneers. Int J Periodontics Restorative Dent. 2013;33(1):31-9.

Gürel G. Porcelain laminate veneers: minimal tooth preparation by design. Dent Clin North Am. 2007;51(2):419-31.

Gürel G. Predictable, precise, and repeatable tooth preparation for porcelain laminate veneers. Pract Proced Aesthet Dent. 2003;15(1):17-24.